Reliability Concerns for HfO2/Si Devices: Interface and Dielectric Traps

TitleReliability Concerns for HfO2/Si Devices: Interface and Dielectric Traps
Publication TypeConference Paper
Year of Publication2002
AuthorsKang, A. Y., P. M. Lenahan, and J. F. Conley
Conference NameIEEE International Integrated Reliability Workshop (IRW)
Pagination102 - 107
Date Published10/2002
Conference LocationLake Tahoe, CA

We have initiated a study of atomic scale defects which may play important roles in the reliability physics of a leading high dielectric constant/Si system: atomic layer deposition (ALD) HfO₂ on silicon. We have utilized capacitance versus voltage and electron spin resonance measurements to explore electrically active defects in ALD HfO₂/Si device structures. We have subjected some of these structures to either vacuum ultraviolet (VUV) illumination or gamma irradiation. The VUV illumination and gamma irradiation flood the dielectric with electrons and holes. Post irradiation measurements most strongly indicate the presence of high densities of large capture cross section electron traps. Electron spin resonance measurements clearly indicate the presence of silicon dangling bond interface defects which are similar to but not identical to the silicon dangling bonds observed at conventional Si/SiO₂ interfaces.